AngularJS上传文件的示例代码

2019-11-19 12:32:29

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使用AngularJS上传文件

前台是Angular页面
后台使用SpringBoot/SpirngMVC

上传文件

html

<div>  <input id="fileUpload" type="file" />  <button ng-click="uploadFile()">上传</button></div>

    $scope.upload = function(){      var form = new FormData();      var file = document.getElementById("fileUpload").files[0];      form.append('file', file);      $http({        method: 'POST',        url: '/upload',        data: form,        headers: {'Content-Type': undefined},        transformRequest: angular.identity      }).success(function (data) {        console.log('upload success');      }).error(function (data) {         console.log('upload fail');      })    }

注意：

AngularJS默认的'Content-Type'是application/json ，通过设置'Content-Type': undefined，这样浏览器不仅帮我们把Content-Type 设置为 multipart/form-data，还填充上当前的boundary，
如果手动设置为：'Content-Type': multipart/form-data，后台会抛出异常：the request was rejected because no multipart boundary was found
boundary 是随机生成的字符串，用来分隔文本的开始和结束
通过设置 transformRequest: angular.identity ，anjularjs transformRequest function 将序列化我们的formdata object，也可以不添加

后台

  @RequestMapping("/upload")  public void uploadFile(@RequestParam(value = "file" , required = true) MultipartFile file) {    //deal with file  }

注意

文件必须通过@RequestParam注解来获取，且需指定value才能获取到

这样就完成了上传文件

上传文件的同时传递其他参数

html

  <div>    <input id="fileUpload" type="file" />    <button ng-click="ok()">上传</button><br>    <input ng-model="user.username" />    <input ng-model="user.password" />  </div>

  $scope.ok = function () {    var form = new FormData();    var file = document.getElementById("fileUpload").files[0];      var user =JSON.stringify($scope.user);    form.append('file', file);    form.append('user',user);    $http({      method: 'POST',      url: '/addUser',      data: form,      headers: {'Content-Type': undefined},      transformRequest: angular.identity    }).success(function (data) {      console.log('operation success');    }).error(function (data) {      console.log('operation fail');    })  };

注意

需要将Object转为String后在附加到form上，否则会直接被转为字符串[Object,object]

后台

  @RequestMapping("/upload")  public Map<String, Object> upload(@RequestParam(value = "file") MultipartFile file, @RequestParam(value = "user", required = true) String user) {    try (FileInputStream in = (FileInputStream) headImg.getInputStream();       FileOutputStream out = new FileOutputStream("filePathAndName")) {      //将Json对象解析为UserModel对象      ObjectMapper objectMapper = new ObjectMapper();      UserModel userModel = objectMapper.readValue(user, UserModel.class);      //保存文件到filePathAndName      int hasRead = 0;      byte[] bytes = new byte[1024];      while ((hasRead = in.read(bytes)) > 0) {        out.write(bytes, 0, hasRead);      }    } catch (IOException e) {      e.printStackTrace();    }  }

注意

ObjectMapper为com.fasterxml.jackson.databind.ObjectMapper

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